This application relates generally to disc drives and recording/reading head interconnects and more particularly to an apparatus for supporting a recording/reading head and assembling a flex circuit in a disc drive.
In a disc drive, a suspension is used to support/suspend a recording/reading head, and an interconnect circuit is used to electrically connect the recording/reading head to disc drive electronics which are disposed away from the recording/reading head.
In general, interconnect circuits fall into three categories, namely: wires, a flex circuit, and integral interconnects. Wire type of interconnect circuits use electrical wires to connect the head to the disc drive electronics. This wire type of interconnect circuits is seldom used any more.
Integral type of interconnect circuits, such as Trace Suspension Assembly (TSA) or Circuit Integrated Suspension (CIS), are fabricated along with a suspension gimbal and are generally a laminate of steel (the gimbal material), polymer (electrical insulator), and copper leads (electrical connection). Integral type of interconnect circuits usually extend from the head, along the suspension, along an actuator arm, and onto a disc drive electronics board where the disc drive electronics are located. Because the copper leads run the entire length of the suspension, the steel backing of the laminate also runs the entire length of the suspension. Such structure may be expensive to manufacture. In addition, the steel material has a relatively stiff structure which keeps the interconnect circuits sensibly in the plane of the suspension during manufacturing because the stiffness and the resulting ability to locate the circuit elements may be an advantage in the manufacturing process.
Flex circuit type of interconnect circuits are a separately fabricated printed circuit that is subsequently assembled to the suspension, e.g. by an adhesive material. The flex circuit is relatively less expensive and easier to manufacture than the integral types of interconnect circuits. In general, a flex circuit is mated to a finished suspension. The flex circuit is quite flexible along its entire length. The head portion of the flex circuit is attached to the suspension. However, the tail portion of the flex circuit is generally not attached to the suspension and hangs freely. FIG. 1 shows a prior art suspension 114 with a flex circuit 110 in a disc drive, wherein the flex circuit 110 is flexible along its entire length. A head portion 112 of the flex circuit 110 is attached to the suspension 114 preferably by a bonding material such as an adhesive material. A tail portion 118 of the flex circuit 110 is flexible and hangs freely. In a subsequent process, usually where the disc drive stack is built, the flexible tail portion 118 has to be manually located and routed to the disc drive electronics. As a result, the assembly of this type of interconnect circuit in a disc drive is difficult to fully automate.
Accordingly, there is a need for a suspension that allows a flex circuit to be assembled in the disc drive in a fully automated fashion.
Against this backdrop the present invention has been developed. The present invention provides a suspension with a stiffener in a disc drive to provide support to a flex circuit, particularly at the tail portion of the flex circuit. The stiffener can be formed in a variety of ways.
In one embodiment of the present invention, an apparatus for a disc drive preferably includes a suspension having a first end and a second end, and a stiffener coupled to the suspension at the second end, the stiffener extending substantially in parallel with the suspension.
The apparatus preferably includes a flex circuit having a first portion and a second portion. The first portion is attached to the suspension, and the second portion is attached to the stiffener. The stiffener extends along the flex circuit.
In a further embodiment, the stiffener is welded to the suspension. Alternatively, the stiffener is integral with the suspension.
In a further embodiment, the stiffener extends towards the second portion of the flex circuit. Alternatively, the stiffener is bent to extend distally from the second end of the suspension.
The suspension preferably includes a load beam. The stiffener is coupled to the load beam.
The present invention also provides a method of fabricating an apparatus for supporting a recording/reading head and assembling a flex circuit in a disc drive. The method includes steps of providing a suspension, and providing a stiffener. The stiffener is coupled to the suspension.
The method preferably includes steps of etching the suspension and the stiffener out of a panel, and orientating the stiffener such that the stiffener extends along the flex circuit. The stiffener is integral with the suspension.
The method preferably includes steps of attaching a first portion of the flex circuit to the suspension, and attaching a second portion of the flex circuit to the stiffener.
In a further embodiment, the step of etching includes a step of etching the suspension and the stiffener out of a carrier strip that is capable of providing a plurality of suspensions and a plurality of stiffeners. The step of orientating the stiffener includes a step of bending the stiffener backwards.
In another embodiment of the present invention, the method preferably includes steps of providing a panel, etching a suspension out of the panel, and attaching a stiffener to the suspension. The step of attaching the stiffener to the suspension preferably includes a step of welding the stiffener to the suspension.
One of the advantages of the present invention is that the stiffener provides support to the flex circuit, particularly at the tail portion of the flex circuit, thereby allowing one to readily locate the flex circuit in the subsequent process, such as a disc drive stack build process. Accordingly, the fabrication of the disc drive can be highly automated.
These and various other features as well as advantages which characterize the present invention will be apparent from a reading of the following detailed description and a review of the associated drawings.